worktree: teach "repair" to fix worktree back-links to main worktree

The .git file in a linked worktree is a "gitfile" which points back to
the .git/worktrees/<id> entry in the main worktree or bare repository.
If a worktree's .git file is deleted or becomes corrupted or outdated,
then the linked worktree won't know how to find the repository or any of
its own administrative files (such as 'index', 'HEAD', etc.). An easy
way for the .git file to become outdated is for the user to move the
main worktree or bare repository. Although it is possible to manually
update each linked worktree's .git file to reflect the new repository
location, doing so requires a level of knowledge about worktree
internals beyond what a user should be expected to know offhand.

Therefore, teach "git worktree repair" how to repair broken or outdated
worktree .git files automatically. (For this to work, the command must
be invoked from within the main worktree or bare repository, or from
within a worktree which has not become disconnected from the repository
-- such as one which was created after the repository was moved.)

Signed-off-by: Eric Sunshine <sunshine@sunshineco.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Eric Sunshine
2020-08-31 02:57:57 -04:00
committed by Junio C Hamano
parent e8e1ff24c5
commit bdd1f3e4da
5 changed files with 175 additions and 1 deletions

View File

@ -98,7 +98,10 @@ with `--reason`.
move::
Move a working tree to a new location. Note that the main working tree
or linked working trees containing submodules cannot be moved.
or linked working trees containing submodules cannot be moved with this
command. (The `git worktree repair` command, however, can reestablish
the connection with linked working trees if you move the main working
tree manually.)
prune::
@ -115,6 +118,11 @@ repair::
Repair working tree administrative files, if possible, if they have
become corrupted or outdated due to external factors.
+
For instance, if the main working tree (or bare repository) is moved,
linked working trees will be unable to locate it. Running `repair` in
the main working tree will reestablish the connection from linked
working trees back to the main working tree.
unlock::